1. Field of the Invention
The present invention pertains to the field of semiconductor integrated circuits. More specifically, the present invention relates to the transferring of integrated circuit devices into and/or out of a plurality of sockets, as may occur during the burn-in process, for example.
2. Description of the Related Art
Integrated circuit devices often must undergo a burn-in process, whereby the devices are operated under accelerated aging conditions to stabilize their circuitry and to detect premature failures. Such accelerated aging conditions may include an elevated temperature (the devices may be baked in an oven), elevated voltage and/or elevated humidity. To start the burn-in process, the devices to be burned in must be removed from a tray or tube onto or in which the devices were placed after manufacturing and loaded onto a burn in board. The burn in board may include a plurality of sockets, which are receptacles that mechanically hold the devices in place and electrically couple the device to be burned to the testing circuitry. In the case of Zero Insertion Force ("ZIF") sockets, the top portion of the sockets (also called the "lid" of the socket) must be pushed down in order to retract the contacts of the socket. The leads of the device may then drop down into corresponding holes in the socket, whereupon the socket lid may be released, causing the socket contacts to come into contact with and bear down on the device leads, thereby mechanically holding and electrically coupling the device to the socket.
Automated loaders exist to load and unload integrated circuit devices into and out of burn in board. Such devices rely upon a so-called preciser, which compensates for any misalignment between the tray on which the devices rest prior to loading and the burn in board sockets. A suction device on the automatic loader picks up the devices from the tray and places them on the preciser. The devices must then be picked up from the preciser and placed within the sockets of the burn in board. The unloading operation follows the opposite sequence: the devices are picked up from the sockets and placed on the preciser, whereupon they are again picked up and placed back upon the tray for later testing. Each of these motions may be considered to be an insertion and automated loaders carry out the equivalent of four insertions. Each such insertion increases the risk that the leads of the device will be bent, which decreases the yield of the overall process. As automated loaders are complex and costly devices (typically costing on the order of several hundreds of thousands of dollars), their suitability must be carefully evaluated, not only in terms of purchasing and maintenance costs, but also in terms of the attendant risk of damaging the leads of the integrated circuit devices to be burned in.
One alternative to such automated loaders is to carry out the device loading and unloading process manually. However, such loading can become tiring for the worker, who must manipulate small outline packages (such as Thin Small Outline Package "TSOP", for example) and corresponding sockets with their fingers without damaging the leads of the devices to be inserted in the sockets. Indeed, the worker must push down the lid of the ZIF socket to retract the socket contacts while simultaneously aligning the device with and pushing the device into the socket. Understandably, damaged leads are a relatively common occurrence when the devices are transferred into and/or out of sockets in this manner.
What are needed, therefore, are devices and methods for transferring of integrated circuit devices into and/or out of a plurality of sockets that are inexpensive and that ease the strain on the workers' fingers as he or she loads and/or unloads the devices from the sockets. Also needed are devices and methods that increase the speed at which integrated circuit devices may be loaded and/or unloaded from a plurality of sockets.